UROGENITAL TRAUMA

American Association for the Surgery of Trauma Organ Injury Scale for kidney Injuries Predicts Nephrectomy, Dialysis, and Death in Patients with Blunt Injury and Nephrectomy for Penetrating Injuries
Kuan JK, Wright JL, Nathens AB, Rivara FP, Wessells H
Department of Urology, University of Washington Medical Center, Seattle, Washington, USA
J Trauma. 2006; 60, 351-5

• Background: Despite broad clinical use of the American Association of the Surgery of Trauma (AAST) injury scale for kidney, it has only been found to predict the need for renal surgery in single institution series. We sought to validate this scheme for morbidity and mortality in a national cohort of patients with renal injury.
• Methods: A retrospective cohort design was used to determine the association between increasing AAST scores and nephrectomy, dialysis, and mortality. The cohort included all patients with a renal injury in the National Trauma Data Bank (NTDB) from 1994 and 2003. Univariate and multivariate prediction models were used for analysis of data.
• Results: At the time of review, a total of 742,774 patient records were registered in the NTDB. Renal injury occurred in 8465 patients (1.2%). Increasing injury grade was associated with a greater nephrectomy (RR 12-127), dialysis (RR 1.3-4.7), and mortality (RR 1.3-1.9) rate for blunt kidney injury. For penetrating injury, nephrectomy was the only outcome that was associated with higher grades of renal injury with a RR of 7.7 to 31 for grades III to V injuries.
• Conclusion: The AAST injury scale for kidney predicts for morbidity in blunt and penetrating renal injury and for mortality in blunt injury. Thus, we continue to support its use as a clinical and research tool.
  
  
• Editorial Comment
  Thee injury scales developed for kidney trauma were primarily based on the consensus of experts in urologic trauma, and not by evidence based medicine. First reported back in 1989, the AAST injury scales provide a valuable tool to classify injuries, in order to perform clinical research, and to decide on management. (1) The above retrospective review is another in a long line of papers seeking to validate that the AAST scale of degree of kidney injury is an accurate predictor of morbidity and mortality from blunt renal trauma. Since the more severe the mechanism of injury, the higher the likelihood for increased AAST renal injury grade, it is intuitive that the kidney and associated injuries result in higher rates of nephrectomy and mortality.
  The National Trauma Data Bank - NTDB - www.facs.org/trauma/ntdb.html - the largest aggregation of trauma registry data ever assembled., managed by the American College of Surgeons, is a national data base of trauma patients admitted to the hospital from over 405 trauma centers, and contains over 1.5 million records from trauma centers in the U.S. and Puerto Rico. The goal of the NTDB is to inform the medical community, the public, and decision makers about a wide variety of issues that characterize the current state of care for injured persons. The NTDB also proves a unique and powerful tool to study national trauma trends as to urologic and general trauma.

Dr. Steven B. Brandes
Associate Professor, Division of Urologic Surgery
Washington University in St. Louis
St. Louis, Missouri, USA